Improve feature flag check for the performance bar

Signed-off-by: Rémy Coutable <remy@rymai.me>

app/controllers/concerns/with_performance_bar.rb

@@ -3,8 +3,6 @@ module WithPerformanceBar
   included do
     include Peek::Rblineprof::CustomControllerHelpers
-    alias_method :performance_bar_enabled?, :peek_enabled?
-    helper_method :performance_bar_enabled?
   end
   def peek_enabled?

app/helpers/performance_bar_helper.rb

+module PerformanceBarHelper
+  # This is a hack since using `alias_method :performance_bar_enabled?, :peek_enabled?`
+  # in WithPerformanceBar breaks tests (but works in the browser).
+  def performance_bar_enabled?
+    peek_enabled?
+  end
+end

config/gitlab.yml.example

@@ -462,7 +462,7 @@ production: &base
   # Performance bar settings
   performance_bar:
     # This setting controls what group can see the performance bar.
-    # allowed_group: performance-group
+    # allowed_group: my-org/performance-group
   #
   # 4. Advanced settings

lib/feature.rb

@@ -60,7 +60,9 @@ class Feature
     def register_feature_groups
       Flipper.register(:performance_team) do |actor|
-        actor.thing&.is_a?(User) && Gitlab::PerformanceBar.allowed_user?(actor.thing)
+        user = actor.thing
+
+        user&.is_a?(User) && Gitlab::PerformanceBar.allowed_user?(user)
       end
     end
   end

lib/gitlab/performance_bar.rb

@@ -21,10 +21,10 @@ module Gitlab
       if RequestStore.active?
         RequestStore.fetch('performance_bar:allowed_group') do
-          Group.by_path(Gitlab.config.performance_bar.allowed_group)
+          Group.find_by_full_path(Gitlab.config.performance_bar.allowed_group)
         end
       else
-        Group.by_path(Gitlab.config.performance_bar.allowed_group)
+        Group.find_by_full_path(Gitlab.config.performance_bar.allowed_group)
       end
     end

spec/lib/gitlab/performance_bar_spec.rb

@@ -74,10 +74,33 @@ describe Gitlab::PerformanceBar do
       let!(:my_group) { create(:group, path: 'my-group') }
       context 'when user is not a member of the allowed group' do
-        it 'returns false' do
+        it 'returns the group' do
           expect(described_class.allowed_group).to eq(my_group)
         end
       end
     end
+
+    context 'when allowed group is nested', :nested_groups do
+      let!(:nested_my_group) { create(:group, parent: create(:group, path: 'my-org'), path: 'my-group') }
+
+      before do
+        create(:group, path: 'my-group')
+        stub_performance_bar_setting(allowed_group: 'my-org/my-group')
+      end
+
+      it 'returns the nested group' do
+        expect(described_class.allowed_group).to eq(nested_my_group)
+      end
+    end
+
+    context 'when a nested group has the same path', :nested_groups do
+      before do
+        create(:group, :nested, path: 'my-group')
+      end
+
+      it 'returns false' do
+        expect(described_class.allowed_group).to be_falsy
+      end
+    end
   end
 end